Commit ed07f635 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/vdso: Use builtin symbols to locate fixup section 



Add builtin symbols to locate fixup section and use them
instead of locating sections through elf headers at runtime.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2954526981859ca1ccfcfc7a7c4263920e9ddfcb.1601197618.git.christophe.leroy@csgroup.eu
parent 91bf6955

arch/powerpc/kernel/vdso.c

+14 −41
Original line number Diff line number Diff line
@@ -434,6 +434,12 @@ static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32, 


#endif /* CONFIG_PPC64 */



#define VDSO_DO_FIXUPS(type, value, bits, sec) do {					\

	void *__start = (void *)VDSO##bits##_SYMBOL(&vdso##bits##_start, sec##_start);	\

	void *__end = (void *)VDSO##bits##_SYMBOL(&vdso##bits##_start, sec##_end);	\

											\

	do_##type##_fixups((value), __start, __end);					\

} while (0)



static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,

					struct lib64_elfinfo *v64)
@@ -530,53 +536,20 @@ static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32, 
static __init int vdso_fixup_features(struct lib32_elfinfo *v32,

				      struct lib64_elfinfo *v64)

{

	unsigned long size;

	void *start;



#ifdef CONFIG_PPC64

	start = find_section64(v64->hdr, "__ftr_fixup", &size);

	if (start)

		do_feature_fixups(cur_cpu_spec->cpu_features,

				  start, start + size);



	start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);

	if (start)

		do_feature_fixups(cur_cpu_spec->mmu_features,

				  start, start + size);



	start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);

	if (start)

		do_feature_fixups(powerpc_firmware_features,

				  start, start + size);



	start = find_section64(v64->hdr, "__lwsync_fixup", &size);

	if (start)

		do_lwsync_fixups(cur_cpu_spec->cpu_features,

				 start, start + size);

	VDSO_DO_FIXUPS(feature, cur_cpu_spec->cpu_features, 64, ftr_fixup);

	VDSO_DO_FIXUPS(feature, cur_cpu_spec->mmu_features, 64, mmu_ftr_fixup);

	VDSO_DO_FIXUPS(feature, powerpc_firmware_features, 64, fw_ftr_fixup);

	VDSO_DO_FIXUPS(lwsync, cur_cpu_spec->cpu_features, 64, lwsync_fixup);

#endif /* CONFIG_PPC64 */



#ifdef CONFIG_VDSO32

	start = find_section32(v32->hdr, "__ftr_fixup", &size);

	if (start)

		do_feature_fixups(cur_cpu_spec->cpu_features,

				  start, start + size);



	start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);

	if (start)

		do_feature_fixups(cur_cpu_spec->mmu_features,

				  start, start + size);



	VDSO_DO_FIXUPS(feature, cur_cpu_spec->cpu_features, 32, ftr_fixup);

	VDSO_DO_FIXUPS(feature, cur_cpu_spec->mmu_features, 32, mmu_ftr_fixup);

#ifdef CONFIG_PPC64

	start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);

	if (start)

		do_feature_fixups(powerpc_firmware_features,

				  start, start + size);

	VDSO_DO_FIXUPS(feature, powerpc_firmware_features, 32, fw_ftr_fixup);

#endif /* CONFIG_PPC64 */



	start = find_section32(v32->hdr, "__lwsync_fixup", &size);

	if (start)

		do_lwsync_fixups(cur_cpu_spec->cpu_features,

				 start, start + size);

	VDSO_DO_FIXUPS(lwsync, cur_cpu_spec->cpu_features, 32, lwsync_fixup);

#endif



	return 0;

arch/powerpc/kernel/vdso32/vdso32.lds.S

+8 −0
Original line number Diff line number Diff line
@@ -38,17 +38,25 @@ SECTIONS 
	PROVIDE(etext = .);



	. = ALIGN(8);

	VDSO_ftr_fixup_start = .;

	__ftr_fixup	: { *(__ftr_fixup) }

	VDSO_ftr_fixup_end = .;



	. = ALIGN(8);

	VDSO_mmu_ftr_fixup_start = .;

	__mmu_ftr_fixup	: { *(__mmu_ftr_fixup) }

	VDSO_mmu_ftr_fixup_end = .;



	. = ALIGN(8);

	VDSO_lwsync_fixup_start = .;

	__lwsync_fixup	: { *(__lwsync_fixup) }

	VDSO_lwsync_fixup_end = .;



#ifdef CONFIG_PPC64

	. = ALIGN(8);

	VDSO_fw_ftr_fixup_start = .;

	__fw_ftr_fixup	: { *(__fw_ftr_fixup) }

	VDSO_fw_ftr_fixup_end = .;

#endif



	/*

arch/powerpc/kernel/vdso64/vdso64.lds.S

+8 −0
Original line number Diff line number Diff line
@@ -39,16 +39,24 @@ SECTIONS 
	PROVIDE(etext = .);



	. = ALIGN(8);

	VDSO_ftr_fixup_start = .;

	__ftr_fixup	: { *(__ftr_fixup) }

	VDSO_ftr_fixup_end = .;



	. = ALIGN(8);

	VDSO_mmu_ftr_fixup_start = .;

	__mmu_ftr_fixup	: { *(__mmu_ftr_fixup) }

	VDSO_mmu_ftr_fixup_end = .;



	. = ALIGN(8);

	VDSO_lwsync_fixup_start = .;

	__lwsync_fixup	: { *(__lwsync_fixup) }

	VDSO_lwsync_fixup_end = .;



	. = ALIGN(8);

	VDSO_fw_ftr_fixup_start = .;

	__fw_ftr_fixup	: { *(__fw_ftr_fixup) }

	VDSO_fw_ftr_fixup_end = .;



	/*

	 * Other stuff is appended to the text segment: